Multiple casting ladle which insures equal volume pouring



y 4. 1967 R. J. WILCOX 3, ,315

MULTIPLE CASTING LADLE WHICH INSURES EQUAL VOLUME POURING Filed March 8, 1965 '2 Sheets-Sheet 1 INVENTOR.

RAYMOND J. WILCOX A TTORNEVS July 4-, i R. J. WILCOX MULTIPLE CASTING LADLE WHICH INSURES EQUAL VOLUME POURING Filed March 8, 1965 2 Sheets-Sheet 2 INVENTOR.

RAYMOND J. WI LCOX www A TTORNEYS United States Patent Ohio Filed Mar. 8, 1965, Ser. No. 437,843 Claims. (Cl. 222144) This invention relates to improvements in apparatus for making brake drums and in particular to apparatus useful in centrifugal casting of the composite type brake drum wherein a braking band of metal is centrifugally cast into and fused to a supporting shell of steel.

An object of the present invention is to provide an improved method of making composite brake drums wherein a plurality of drums are simultaneously centrifugally cast as separate entities to thereby reduce manufacturing costs and increase uniformity of product.

Another object of the present invention is to provide an improved casting ladle of simplified and economical construction particularly adapted for use in the foregoing method of the invention which insures that equal volumes of metal are poured into each of the plurality of individual drums being simultaneously centrifugally cast.

Other objects, features and advantages of the present invention will become apparent from the following detailed description and accompanying drawings wherein:

FIG. 1 is a perspective view of the casting ladle of the present invention.

FIG. 2 is a sectional view on the line 2-2 of FIG. 1 illustrating the casting ladle in a tilted pouring position.

FIG. 3 is a seotionnal view corresponding to that of FIG. 2 but illustrating the ladle in an upright filling position, and

FIG. 4 is a longitudinal sectional view through a centrifugal casting apparatus illustrating the use of the casting ladle in simultaneously pouring molten metal into the supporting shells of two brake drums in accordance with the method of the invention,

Referring to FIGS. 1-3, the illustrated embodiment of a casting ladle of the present invention comprises a trough-like container adapted to receive and dispense molten metal. Ladle 10 is shown by way of illustration in the form of a generally rectangular trough with outwardly slanted front and rear walls 12 and 14 respectively which are joined by a pair of end walls 16 and 18 and by a bottom wall 20 (FIGS. 2 and 3). Walls 12- 20 define a compartment open at the top and adapted to receive molten metal therein. For this purpose walls 12-20 of ladle 10 may be made of a metal having high strength and a higher melting point than cast iron, and the inner surfaces of these walls lined with a suitable refractory material to provide the refractory lining 22 illustrated in section in FIGS. 2 and 3.

In accordance with one feature of the present invention, the open compartment of ladle 12 is divided into subcompartments 24 and 26 (FIGS. 1 and 4) by an upright partition 28 which extends from wall 12 to wall 14 of the ladle and is joined in liquid tight relation to these walls as well as to bottom wall 20. Partition 28 has an upper edge which comprises a first portion 30 extending horizontally in the upright position of the ladle (FIG. 3) flush with the upper edge 32 of front 12. Approximately midway between the front and rear walls, upper edge 30 meets a second portion 34 which tapers downwardly so that it meets rear wall 14 at a point disposed below the overflow level 36 of the molten metal in the ladle when the ladle is in the upright filling position of FIG. 3. Partition 28 is thus shaped to function as an overflow weir between subcompartments 24 and 26 when the ladle is upright (FIG. 3) and when the level of the liquid in compartment 26 has reached the junction of edge 34 and back wall 14, When a further rise in the liquid level occursin compartment 26, metal will thereafter overflow from compartment 26 into compartment 24 through the triangular area defined by the lines 36, 34 and the lining 22 as illustrated in FIG. 3.

The overflow level 36 is established by a pair of pouring lips 38 and 40 which are formed at the same elevation in the upper edge 32 of front wall 12 to respectively communicate with subcompartments 24 and 26. The refractory wall lining 22 also covers pouring lips 38 and 40. Lips '38 and 40 preferably consist of rectangular notches in the edge 32 which are of equal area in the plane of wall 32 and oriented so that they remain in horizontal alignment in both the pouring and filling positions of ladle 10.

Ladle 10 also includes a sprue arm 42 joined to the rear corner of compartment 26 and extending rearwardly and at an angle of about 60 to the longitudinal axis of the ladle. Arm 42 has a channel 44 which empties into compartment 26 to facilitate filling of the ladle from a holding pot.

While ladle 10 may be supported by various types of support structures, when used with the centrifugal casting apparatus shown in FIG. 4 it is preferably cantilever supported at one end by a shaft 44 (FIG. 4) which has a mounting flange 46 suitably secured to end wall 16 of ladle 10 as by bolts or weldinng. The position of the shaft 44 .and flange 46 is indicated in phantom in FIGS. 2 and 3. Suitable apparatus is provided to support the end of shaft 44 remote from the ladle (not shown) for rotation of the shaft about its axis 48 to thereby rotate ladle 10 about the same axis (FIGS. 2

o and 3).

In accordance with the method of the present invention, two or more single and separate steel hoops are fabricated, as by rolling, to the cross-sectional configuration shown in FIG. 4 to provide two or more preformed shells 50 and 52 for the ring of the brake drum. While only two shells 50 and 52 are shown, it is to be understood that the invention also contemplates providing a plurality (two or more) of sheet metal shells each of which is preformed in the above manner so as to have radially inwardly extending circumferential flanges 54, 56 and 58,, 60 at the opposite ends of the respective bands. After providing two or more of such shells, the method of the invention contemplates the temporary securement of shells 50 and 52 together in end to end relation and coaxial alignment as shown in FIG. 4. Preferably the shells are temporarily attached to one another by brazing flange 56 to flange 58 with a suitable brazing metal having a metal point above a predetermined temperature to which the shell is preheated as described hereinafter, but less than the higher temperature to which the shell is heated by the molten metal when the same is centn'fugally cast into the shell as described hereinafter. Attaching the preformed shells together in this manner permits handling of the plurality of shells as a unit inn both of the subsequently described preheating and chuck loading steps.

After the shells have been temporarily secured together in side by side coaxial relation, they are coated with a suitable powdery flux and then placed in an electrical induction or other suitable heater where they are heated to a predetermined preheat temperature. The shells are then removed from the induction heater and while still hot are loaded in the opened taper chuck jaws 62 and 64 of the centrifugal casting apparatus shown in FIG. 4, which may be a known apparatus such as that illustrated in the United States Campbell 2,153,173 patent. Jaws 62, 64 are slidably actuated in the conical bore of an outer pilot chuck member 66 by a spider 68 secured to a slidable shaft 70, and also by an annular head 72 secured to aslidable shaft 74, as is well known in the art.

Concurrently with the above preheating and loading steps ladle is filled? with the. molten back lining metal, such as a' suitable cast iron, to be poured into backs 50 and. 52. This is done by pouring the molten metal from a holding pot into channel 44 of sprue arm 42 so that the molten metal first fills subcompartment 26 to the level of the intersection of edge 34 and wall 14, ladle 10. being disposed horizontally during filling as illustrated in FIG. 3. A further amount of molten metal is introduced into subcompartment 26, causing the molten metal therein to flow from subcompartment 26 over edge 34 into subcompartment 24-. When subcompartment 26 is filled to the level of the metal in subcompartment 26, as indicated by the line 76 in FIG. 3, the flow of metal to the ladle is shut off.

The ladle is then transferred to the chuck and introduced endwise axially into the chucked shells 50 and 52 While in the upright position of FIG. 3 until lips 38- and 40 are respectively oriented in transverse alignment with shells 50' and 52' as shown in FIG. 4. Then chuck 66 is rotated to thereby rotate shells 50 and 52 about their axes. When centrifugal casting rotational speed has been reached, ladle 10 is tilted from the upright position of FIG. 3 to the initial pouring position of FIG. 2 by rotating it about the axis 48. As the ladle is thus being tilted to the pouring position, the inclined edge 34 of partition 28 rises to the position shown in FIG. 2 wherein edge 34 is disposed above the level 76'of the liquid in subcompartments 24 and 26. It is to be noted that the brink of lip 40 is oriented relative to edge 34 such that edge 34 surfaces prior to the molten metal spilling. over lip 40.

Thus by the time the ladle has been tilted sufliciently to commence pouring molten metal, partition 28- is disposed to block flow of the molten metal between the subcompartments of the ladle, thereby trapping an equalvolume of molten metal in each of the subcompartments 24 and 26. When the ladle is tilted further to start the molten metal flowing over lips 38 and 40, the molten metal will commence flowing in individual streams 80 and 82 from compartments 24 and 26 respectively into the rotating shells 50' and 52 to thereby line them with the molten metal.

After subcompartments 24 and 26 have-been emptied of molten metal, the empty ladle is withdrawn endwise from the lined shells and chuck. Rotation of the chuck is thereafter continued until the molten metal has solidified in shells 50 and 52. In the final step of the method rotation of the chuck is stoppedand the centrifugally lined shells are individually removed from the chuck, the shells being readily separated from one another due to detachment by melting of their brazed attachments in the casting step. The lined shells are then ready for. subsequent machining, as required, followed by attachment of the usual back to one of the flanges 54, 56 of the finished drum ring to thereby provide a finished brake drum;

From the foregoing description, it will now be apparent that the method of the invention permits simultaneous pouring of two or more composite type brake rings While eliminating the cost of. subsequently parting the poured rings one from another as well as the wasted material involved in the parting step and the subsequent machining of the lining material to provide the. securement flange at one end of the drum.

' The present invention also provides a novel pouring ladle 10-which automatically insures that equal volumes of molten metal are poured into the respective individual shells. This result is obtained by subdividing the ladle into equal volume compartments when in-the filling posi- .4 tion, as by the provision of partition 28, which is shaped to cut off communication between the subcompartments during pouring. Upon tilting, equal volumes of metal are trapped in the subcompartments, thereby eliminating diiferences in the respective quantities poured into the shells which would otherwise result from such factors as differences in the elevation and cross-sectional area of pouring lips 38 and 40 resulting from erosion of the refractory lining material 22, lack of precision in making the ladle and lack of rigid and accurate support for the ladle due to the cantilever type support 44.

It is to be understood that the casting ladle 10 of the present invention may be suitably modified for pouring more than two drums simultaneously, as by lengthening the ladle so that it is substantially coextensive in length with the end to end assembly of preformed shells and subdivided by provision of additional partitions 28 suitably located in accordance with the above principles to provide equal volume subcompartments adapted for registry with the associated shell in the pouring step.

I claim:

1. A casting ladle having a trough-like compartment adapted to receive molten metal, at least two pouring lips communicating with the upper area of said compartment, means for supporting said ladle for rotation about an axis between an upright position for receiving molten metal therein and a tilted position for pouring metal therefrom via said pouring lips, and a partition in said compartment disposed generally transversely to said axis dividing said compartment into first and second subcompartments, said pouring lips communicating one with each subcompartment, said partition being shraped to form an overflow weir between said subcompartments when said ladle is in said upright position and to prevent flow therebetween when said ladle is tilted for pouring metal therefrom.

2. The ladle set forth in claim- 1 wherein said subcompartments have substantially equal volumes up to the level of said' overflow weir in the upright position of. said ladle.

3. The ladle set forth in claim 1 wherein said one of said subcompartments has a channel-shaped arm extending therefrom generally oppositely to the pouring lip and adjacent the upper edge of said subcompartment for directing molten metal into said one subcompartment.

4. The ladle set forth in claim 3 wherein said arm is disposed adjacent one end of said ladle and saidsupport means comprises a shaft secured to said one end of said ladle and extending away from said ladle coaxially with said axis of rotation of said ladle.

5'. The ladle set forth in claim 1 wherein said partition means has an upper edge extending horizontally in the upright position of said ladle above the level of said pouring lips for about half the distance between the pour lips and an opposite wall of said compartment and then tapers downwardly to a point of intersection with said opposite wall, the tapering portion of said upper edge defining said overflow weir.

References Cited UNITED STATES PATENTS 429,337 6/1890 Collin 2281 1,820,597 8/ 1931' Colwell 22- 84 3,203,689 '8/ 1965 Hallowell 2285 FOREIGN PATENTS 732,078 6/ 1955 Great Britain.

1. SPENCER OVERHOLSER, Primary Examiner.

R. D. BALDWIN, Assistant Examiner. 

1. A CASTING LADLE HAVING A TROUGH-LIKE COMPARTMENT ADAPTED TO RECEIVE MOLTEN METAL, AT LEAST TWO POURING LIPS COMMUNICATING WITH THE UPPER AREA OF SAID COMPARTMENT, MEANS FOR SUPPORTING SAID LADLE FOR ROTATION ABOUT AN AXIS BETWEEN AN UPRIGHT POSITION FOR RECEIVING MOLTEN METAL THEREIN AND A TILTED POSITION FOR POURING METAL THEREFROM VIA SAID POURING LIPS, AND A PARTITION IN SAID COMPARTMENT DISPOSED GENERALLY TRANSVERSELY TO SAID AXIS DIVIDING SAID COMPARTMENT INTO FIRST AND SECOND SUBCOMPARTMENTS, SAID POURING LIPS COMMUNICATING ONE WITH EACH SUBCOMPARTMENT, SAID PARTITION BEING SHRAPED TO FORM AN OVERFLOW WEIR BETWEEN SAID SUBCOMPARTMENTS WHEN SAID LADLE IS IN SAID UPRIGHT POSITION AND TO PREVENT FLOW THEREBETWEEN WHEN SAID LADLE IS TILTED FOR POURING METAL THEREFROM. 